The new World Health Organization and Joint United Nations Programme on HIV/AIDS strategic framework for voluntary medical male circumcision (VMMC) aims to increase VMMC coverage among males aged 10–29 years in priority settings to 90% by 2021. We use mathematical modeling to assess the likelihood that selected countries will achieve this objective, given their historical VMMC progress and current implementation options.

Scaling Up Voluntary Medical Male Circumcision for Human Immunodeficiency Virus Prevention for Adolescents and Young Adult Men: A Modeling Analysis of Implementation and Impact in Selected Countries

CID
Scaling Up Voluntary Medical Male Circumcision for Human Immunodeficiency Virus Prevention for Adolescents and Young Adult Men: A Modeling Analysis of Implementation and Impact in Selected Countries
0 Palladium Group
1 Independent Consultant , Geneva , Switzerland
2 Office of HIV/AIDS, Global Health Bureau, United States Agency for International Development , Washington, District of Columbia , USA
3 Emmanuel Njeuhmeli
4 Department of Health, Behavior and Society, Johns Hopkins Bloomberg School of Public Health , Baltimore, Maryland , USA
5 Johns Hopkins Center for Communication Programs
6 Avenir Health , Washington, District of Columbia , USA
Background. The new World Health Organization and Joint United Nations Programme on HIV/AIDS strategic framework for voluntary medical male circumcision (VMMC) aims to increase VMMC coverage among males aged 10-29 years in priority settings to 90% by 2021. We use mathematical modeling to assess the likelihood that selected countries will achieve this objective, given their historical VMMC progress and current implementation options. Methods. We use the Decision Makers' Program Planning Toolkit, version 2, to examine 4 ambitious but feasible scenarios for scaling up VMMC coverage from 2017 through 2021, inclusive in Lesotho, Malawi, Mozambique, Namibia, South Africa, Swaziland, Tanzania, Uganda, and Zimbabwe. Results. Tanzania is the only country that would reach the goal of 90% VMMC coverage in 10- to 29-year-olds by the end of 2021 in the scenarios assessed, and this was true in 3 of the scenarios studied. Mozambique, South Africa, and Lesotho would come close to reaching the objective only in the most ambitious scenario examined. Conclusions. Major changes in VMMC implementation in most countries will be required to increase the proportion of circumcised 10- to 29-year-olds to 90% by the end of 2021. Scaling up VMMC coverage in males aged 10-29 years will require significantly increasing the number of circumcisions provided to 10- to 14-year-olds and 15- to 29-year-olds.
-
Voluntary medical male circumcision (VMMC) is a highly
effective [
1–3
] and cost-effective [
4–6
] intervention to reduce
femaleto-male human immunodeficiency virus (HIV) transmission. It
is recommended in countries with high HIV prevalence and low
levels of male circumcision [
7, 8
]. Fourteen countries in
sub-Saharan Africa are scaling up service delivery of adult VMMC for
HIV prevention [9]. In 2011, the World Health Organization
(WHO) and the Joint United Nations Programme on HIV/AIDS
(UNAIDS) released a strategic framework outlining VMMC
implementation objectives in priority countries [
9
]. The strategy
set a target of reaching VMMC coverage of at least 80% among
males aged 15–49 years by 2015. Modeling conducted in 2011
to inform this strategy indicated that >20 million males aged
15–49 years would need to be circumcised between 2011 and
2015 to increase the proportion of circumcised men in this age
group to 80% [
6
]. By the end of 2015, almost 12 million men and
adolescent boys had been circumcised [
10
].
More recently, in the context of plateauing global resources
for HIV services [
11
] and international commitment to respond
more effectively to the epidemic [
7, 12–15
], additional
modeling was conducted to inform country prioritization of VMMC
scale-up [
16–24
]. Two main insights emerged from these
analyses. First, to focus limited resources, countries are transitioning
from national scale-up of VMMC service provision to focused
scale-up in a subset of priority subnational locations. Second, in
addition to this geographical prioritization, countries are
framing their scale-up targets around reaching high coverage among
younger men and adolescent boys. Increasing the proportion of
circumcised 15- to 29-year-olds will produce the most
immediate impact on HIV incidence [
16–24
] compared to circumcising
other age groups. Increasing VMMC coverage in younger
adolescent boys aged 10–14 years contributes to increasing the
proportion of circumcised 15- to 29-year-olds in the near term and
it takes advantage of existing demand for VMMC among
10to 14-year-olds. Whereas the roll-out of VMMC programs has
not specifically focused on attracting this age group, more than
a third of clients accessing VMMC services to date have been
younger adolescents aged 10–14 years, among whom
circumcision is socially and culturally most acceptable [
25, 26
]. Indeed
the new WHO/UNAIDS strategic framework for VMMC aims
to increase VMMC coverage among males aged 10–29 years in
priority settings to 90% by 2021 [10].
In this article, we use mathematical modeling to examine
the impact of 4 hypothetical scenarios for VMMC program
implementation from 2017 through 2021. We explore the
ways in which annual uptake of circumcision in various age
groups between 2017 and 2021, inclusive, could affect the
proportion of circumcised males aged 10–29 years by the end
of 2021. Our analyses focus on 9 of the 14 priority countries
scaling up VMMC for HIV prevention: Lesotho, Malawi,
Mozambique, Namibia, South Africa, Swaziland, Tanzania,
Uganda, and Zimbabwe. The purpose of this analysis is to
assess the likelihood that these countries will increase the
proportion of circumcised 10- to 29-year-olds to 90% by the
end of 2021, given their historical VMMC progress and
current implementation options.
METHODS
We used the Decision Makers’ Program Planning Toolkit
(DMPPT), version 2, to examine 4 scenarios for scaling up
VMMC coverage from 2017 through 2021. Our analyses are
limited to those countries for which age-disaggregated
program data were available for all years of the VMMC program,
which excluded 5 of the 14 priority countries scaling up VMMC
for HIV prevention (Botswana, Ethiopia, Kenya, Rwanda, and
Zambia) from this study.
Decision Makers’ Program Planning Toolkit 2 Model
The DMPPT 2 model, described in depth elsewhere [
22, 26
],
has been used extensively to assess the epidemiological impact
and cost-effectiveness of circumcising different age groups of
VMMC clients. In brief, the DMPPT 2 model is a simple
compartmental model implemented in Microsoft Excel 2010. The
model tracks the number of males circumcised as newborns
and in each 5-year age group over time, taking into account
age progression and mortality. The model also calculates
discounted VMMC program costs and HIV infections averted in
the population in each year of user-specified VMMC scale-up
strategies. These are compared to a baseline scenario in which
male circumcision prevalence is held constant at the level found
prior to the initiation of VMMC services for HIV prevention.
Data Sources
Key model inputs for Lesotho, Malawi, Mozambique, Namibia,
Swaziland, South Africa, Tanzania, Uganda, and Zimbabwe
can be found in the Supplementary Appendix 1. The DMPPT
2 model is populated with population, mortality, and HIV
incidence and prevalence projections from an external source.
Population by age and year, mortality by age and year, annual
number of male births, and HIV prevalence by age and year
were exported from Spectrum/Goals or Spectrum/AIDS
Impact Model (AIM) files for all countries [27]. The HIV
incidence was also obtained from Spectrum/Goals or Spectrum/
AIM files for all countries except Swaziland. For Swaziland, the
age-specific HIV incidence was derived from the Swaziland
Incidence Measurement Survey [
28
]. The male circumcision
prevalence by age group in the model’s base years for each
country was derived from Demographic and Health Surveys
or AIDS Indicator Surveys from the most recent years before
the start of the VMMC program. Information on the annual
number of male circumcisions performed since the beginning
of the program was obtained from WHO and the age
disaggregation of the annual number of VMMCs performed was
estimated using the US President’s Emergency Plan for AIDS
Relief (PEPFAR) annual reporting [
26
].
Scenarios Analyzed
We explored 4 hypothetical scale-up scenarios representing
ambitious but feasible VMMC program implementation
objectives, given historical trends in scaling up male circumcision in
countries. We defined “aggressive” scale-up as multiplying the
numbers of circumcisions performed in 2016 by 1.5 and
performing that number of circumcisions annually between 2017
and 2021, inclusive. We defined “very aggressive” scale-up as
doubling the numbers of circumcisions performed in 2016 and
performing that number of circumcisions annually from 2017
through 2021. In scenario 1, no circumcisions were performed
in young adolescent boys aged 10–14 years, and the annual
number of circumcisions performed in men aged 15–29 years
from 2017 through 2021 was equal to the number of VMMCs
performed in 2016. In scenario 2, the annual number of
circumcisions performed in boys and men aged 10–29 years from 2017
through 2021 was equal to the number of VMMCs performed
in 2016. In scenario 3, the annual number of circumcisions
performed in boys aged 10–14 years from 2017 through 2021
was equal to the number of VMMCs performed in 2016 and
the number of VMMCs in men aged 15–29 years was scaled up
aggressively. In scenario 4, the annual number of VMMCs in
boys aged 10–14 years was scaled up aggressively and the
number of circumcisions in men aged 15–29 years was scaled up very
aggressively. In all 4 scenarios, the annual number of
circumcisions performed in men aged 30–39 years was kept constant at
2016 levels. The numbers of male circumcisions projected in
each of the 4 scenarios are shown in Supplementary Table 1.
RESULTS
The numbers of male circumcisions that would be performed
from 2017 through 2021 in the 4 scenarios described above are
shown in Figure 1 for each country and age group. Figure 1 also
compares these to the numbers of circumcisions performed
Scaling Up VMMC for Boys and Young Men • CID 2018:66 (Suppl 3) • S167
since the beginning of the VMMC programs in each country
and the age distribution of the VMMCs performed to date.
Supplementary Figure 1 shows the annual numbers of male
circumcisions performed in scenario 4 and compares these to the
annual numbers of circumcisions performed since the
beginning of the VMMC programs in each country. These figures
highlight that there are notable differences across countries
in the age distributions of VMMCs provided to date and that
not performing circumcisions in the 10- to 14-year age group
would affect countries differently. Whereas circumcisions of
boys aged 10–14 years have made up just 5% of all
circumcisions performed to date in Namibia, the proportion of VMMCs
performed in this age group has been between 30% and 50%
in Lesotho, Malawi, Mozambique, Tanzania, Uganda, and
Zimbabwe. These figures also underline that the vast majority
of VMMCs performed to date have been circumcisions of
adolescent boys aged 10–19 years. Seventy percent or more of all
VMMCs performed in Lesotho, Malawi, Mozambique, South
Africa, Tanzania, Uganda, and Zimbabwe have been of
adolescent boys aged 10–19 years.
Figure 2 shows the proportion of circumcised males aged
15–29 and 10–29 years in the population by the end of 2021
S168 • CID 2018:66 (Suppl 3) • Njeuhmeli et al
for each of the 4 scenarios. Figure 2 also compares these to the
male circumcision coverage in these age groups at baseline and
by the end of 2016. Figure 2 illustrates that providing
circumcisions to boys aged 10–14 years would lead to increased VMMC
coverage in the 15- to 29-year age group. In addition, focusing
on the 10- to 29-year age group, not conducting any VMMCs in
boys aged 10–14 years and holding constant the annual
number of VMMCs in men aged 15–29 years at 2016 levels
(scenario 1) would lead to proportions of circumcised males aged
10–29 years in the population by the end of 2021 that range
from 14% in Malawi to 73% in Tanzania. Holding constant the
annual number of VMMCs in boys and men aged 10–29 years
at 2016 levels (scenario 2) would lead to proportions of
circumcised males aged 10–29 years in the population by the end
of 2021 that range from 18% in Malawi to 93% in Tanzania.
Aggressively increasing the annual number of circumcisions
of 15- to 29-year-olds and holding constant the annual
number of VMMCs of boys aged 10–14 years at 2016 levels
(scenario 3) would lead to proportions of circumcised males aged
10–29 years in the population by the end of 2021 of ≥60%
in Lesotho, Mozambique, South Africa, and Tanzania. Very
aggressively increasing the annual number of circumcisions of
15- to 29-year-olds and aggressively increasing the number of
circumcisions of 10- to 14-year-olds (scenario 4) would lead to
proportions of circumcised males aged 10–29 years in the
population by the end of 2021 of ≥60% in Lesotho, Mozambique,
South Africa, Tanzania, Uganda, and Zimbabwe. This
proportion would be ≥80% by the end of 2021 in Mozambique, South
Africa, and Tanzania and ≥90% only in Tanzania.
Figure 3 shows historical male circumcision coverage by age
group at the end of each year from the beginning of the VMMC
program through 2016 and the projected annual year-end
coverage through the end of 2021 for scenario 4, underlining the
contribution of historical coverage in each age group to the
current and future coverage of male circumcision. Baseline VMMC
coverage in most age groups was higher in those countries
projected to reach the highest coverage levels by the end of 2021,
including Lesotho, Mozambique, South Africa, Tanzania, and
Uganda.
Table 1 shows the number of HIV infections averted from 2008
through 2025 for each of the 4 scenarios. Whereas scenario 1 led
to the smallest number of HIV infections averted in each country,
scenario 4 produced the largest number. Providing circumcisions
to adolescent boys aged 10–14 years increases both male
circumcision coverage and VMMC’s impact on HIV infections averted.
DISCUSSION
The analyses presented in this paper reveal that significant
changes in VMMC implementation in most countries will
be required to increase the proportion of circumcised 10- to
29-year-olds to 90% by the end of 2021. We explored
hypothetical scale-up scenarios representing ambitious but feasible
VMMC implementation objectives, given historical trends in
scaling up annual uptake of male circumcision. Tanzania is the
only country studied that would reach the goal of 90% VMMC
coverage in 10- to 29-year-olds by the end of 2021. It could
achieve this goal by maintaining constant the annual number
of VMMCs in boys and men aged 10–29 years at 2016 levels
(scenario 2). The second country that would come close to
reaching the WHO/UNAIDS objective is Mozambique, where
very aggressively increasing the annual number of
circumcisions of 15- to 29-year-olds and aggressively increasing the
annual number of VMMCs in boys aged 10–14 years (scenario
4) would lead to 86% VMMC coverage in 10- to 29-year-olds
by the end of 2021. South Africa would reach 80% coverage
among 10- to 29-year-olds by the end of 2021 in scenario 4 and
Lesotho would get close to reaching 80% coverage among 10- to
29-year-olds in this scenario.
Our work highlights the importance of historical
numbers of circumcisions conducted and coverage levels in each
age group to current and future male circumcision coverage.
Baseline VMMC coverage in most age groups was highest in
the countries projected to reach or come close to reaching the
WHO/UNAIDS target coverage levels by 2021—Tanzania,
Mozambique, Lesotho, and South Africa. It is also
noteworthy that Tanzania, the only country studied that would reach
the WHO/UNAIDS target coverage by 2021, is unique in that
it has had a focused approach to scaling up VMMC since the
beginning of its program [
23
]. The Tanzania National VMMC
Program has been focusing on scaling up VMMC service
delivery to males aged 10–34 years since it was launched in 2010 even
though the international guidance at the time recommended
Scaling Up VMMC for Boys and Young Men • CID 2018:66 (Suppl 3) • S169
scaling up services to males aged 15–49 years [
9
]. Conversely,
VMMC coverage levels in certain countries, including Malawi,
Namibia, and Swaziland, have been and continue to be so low
that attaining WHO/UNAIDS target coverage levels is unlikely
without significant strategic changes in both demand creation
and service delivery.
The figure shows total human immunodeficiency virus infections averted from 2008
through 2025 for the 4 scenarios. In scenario 1, no voluntary medical male circumcisions
(VMMCs) of boys aged 10–14 years are performed and the annual number of VMMCs of
men aged 15–29 years is held constant at 2016 levels. In scenario 2, the annual number
of VMMCs of 10- to 29-year-olds is held constant at 2016 levels. In scenario 3, the annual
number of VMMCs of boys aged 10–14 years is held constant at 2016 levels, we increase
by 50% the number of VMMCs of men aged 15–29 years in 2016, and those numbers
are maintained each year thereafter. In scenario 4, we increase by 50% the number of
VMMCs of boys aged 10–14 years in 2016 and double the number of VMMCs of men aged
15–29 years in 2016, and those numbers are held constant from 2017 to 2021, inclusive.
S170 • CID 2018:66 (Suppl 3) • Njeuhmeli et al
Looking forward, these analyses also show the importance of
scaling up VMMC services to adolescent boys aged 10–19 years
and especially of ensuring that circumcision programs include
young adolescent boys aged 10–14 years. Most of the VMMCs
performed to date have been circumcisions of adolescent boys aged
10–19 years and more than a third of clients accessing VMMC
services have been young adolescent boys aged 10–14 years even
though roll-out of VMMC programs has not focused on
appealing to this age group in most countries. Given the high demand
for services in the 10- to 14-year age group in most countries
and the limited demand for VMMC in men aged ≥20 years [
29
],
increasing VMMC coverage in younger adolescent boys aged
10–14 years takes advantage of cultural preferences and existing
demand for VMMC in this age group. Changing demand creation
and service delivery strategies to explicitly focus on boys aged
10–14 years could lead to further increases in demand for VMMC
in young adolescent boys. Notably, providing circumcisions to
adolescent boys aged 10–14 years increases male circumcision
coverage in the 10- to 29-year age group and in the 15- to 29-year
age group as well as increasing VMMC’s impact on HIV infections
averted. Scaling up VMMC coverage in men aged 10–29 years to
90% will require significantly increasing the number of
circumcisions provided to both 15- to 29-year-olds and 10- to 14-year-olds.
A number of limitations should be kept in mind when
interpreting our findings. The DMPPT model’s limitations have been
described in detail elsewhere [
22
]. The model relies on available
national and subnational demographic, epidemiological, and
program data and estimates of varying quality and
completeness. The main limitation of this work is its reliance on
program data. We sought to apply scale-up scenarios representing
feasible VMMC program implementation objectives given 2016
program accomplishments and historical scale-up trends. In
addition, due to data availability, our analysis is limited to 9 of
the 14 VMMC priority countries supported by PEPFAR.
Although our analysis does not address the financial and other
resource implications of each scenario, assessments of existing
site capacity reveal that many sites are operating below capacity.
Previous work identified substantial differences in unit costs of
VMMC within and among countries, indicating that substantial
efficiency gains could be made in VMMC service delivery [
30
]. In
one study, average efficiency scores ranged from 51% in Zambia to
70% in South Africa [
31
]. As a result, 10- to 14-year-olds
presenting for circumcision in the absence of tailored demand creation
programs are readily being accommodated in most settings within
the confines of current budgets, and many sites have the capacity
to accommodate additional clients. Furthermore, the
popularity of male circumcision among adolescents this age, along with
growing evidence that adolescent girls and young women are
expressing preference for circumcised sexual partners [
32
], may
be creating new social norms that could also influence their older
peers aged 15–29 years to come forward for VMMC services.
In conclusion, our analysis has important implications for
countries and their international partners as they consider next
steps in VMMC implementation to meet the WHO/UNAIDS
target. Our study highlights that most countries will not
increase the proportion of circumcised 10- to 29-year-olds to
90% by 2021 without significant changes in VMMC
implementation. The likelihood of countries achieving the 2021 target is
influenced partly by the historical numbers of circumcisions
conducted and coverage levels attained, and some countries are
unlikely to reach WHO/UNAIDS target coverage levels
without significant strategic changes in both demand creation and
service delivery. Scaling up VMMC coverage in males aged
10–29 years will require increasing the number of
circumcisions provided to 10- to 14-year-olds and 15- to 29-year-olds.
Supplementary Data
Supplementary materials are available at Clinical Infectious Diseases online.
Consisting of data provided by the authors to benefit the reader, the posted
materials are not copyedited and are the sole responsibility of the authors,
so questions or comments should be addressed to the corresponding author.
Notes
Acknowledgments. The authors thank John Stover of Avenir Health,
who developed the DMPPT 2 model at the request of the US Agency for
International Development (USAID), under the USAID-funded Health
Policy Project. The authors also thank Matt Hamilton of Avenir Health for
his work in updating the model version used for this manuscript.
Disclaimer. The information provided does not necessarily reflect the
views of USAID, PEPFAR, or the US government, and the contents of this
article are the sole responsibility of projects Supporting Operational AIDS
Research (SOAR) and AIDSFree, the Population Council, and the authors.
Financial support. This manuscript was made possible by the
generous support of the American people through PEPFAR with USAID under
the cooperative agreement project SOAR (number AID-OAA-14-00026),
and cooperative agreement Strengthening High Impact Interventions for an
AIDS-Free Generation (number AID-OAA-A-14-00046).
Supplement sponsorship. This article appears as part of the supplement
“Adolescent Voluntary Medical Male Circumcision: Vital Intervention Yet
Improvements Needed,” sponsored by Johns Hopkins University.
Potential conflicts of interest. All authors: No reported conflicts.
All authors have submitted the ICMJE Form for Disclosure of Potential
Conflicts of Interest. Conflicts that the editors consider relevant to the
content of the manuscript have been disclosed.
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